UPDATE: It has now been confirmed that the clip is promoting an upcoming stage revival of Harold Pinter's play Betrayal, starring Hiddleston. The play will debut at the Harold Pinter Theatre in London on March 5, 2019, for a limited 12 week run. Click here for more information.

Original article follows.

Actor Tom Hiddleston made a rare appearance on Twitter, sharing a mysterious clip from an upcoming project called Betrayal. While the clip wasn't accompanied by a caption or explanation, some fans have speculated that Hiddleston is appearing in a new take on Harold Pinter's play Betrayal, about infidelity between two married couples.

Hiddleston is best known for his role as Thor's mischievous brother Loki in the Marvel Cinematic Universe, most recently appearing in this summer's Avengers: Infinity War. He's set to reprise the role in a new Loki-oriented TV show, which will make its debut on Disney's upcoming streaming service, Disney Plus. In the meantime, though, it looks like Hiddleston has been keeping busy with other projects.

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The actor recently took to Twitter for the first time this year to confirm the Loki TV show and promise "more mischief to make," and now he's tweeted for the second time in 2018, sharing a cryptic minute-long clip of himself walking down a neon-lit tunnel covered in graffiti (including Elmo!) and looking tearfully ahead. The clip simply ends with the word "Betrayal" flashing up on screen, leading fans to speculate that Hiddleston is returning to the stage for Pinter's play.

Pedestrian pointed out that Hiddleston appears to be wearing the same outfit in the above clip that he wore at an event promoting a season of Pinter plays at the Harold Pinter Theatre in London. In the interview clip below, the actor can be seen praising the playwright's works. Interestingly, Betrayal is not one of the plays scheduled for the "Pinter at the Pinter" season, which began in September and will run through to February 2019, so it's possible that Betrayal has been secretly added to the showcase.

Hiddleston began his career performing on the West End in London, and has continued to find time for stage work in between TV shows and blockbuster movies, most recently playing the titular role in Kenneth Branagh's stage production of Hamlet. Given his enthusiasm for Pinter's work, it wouldn't be at all surprising if Hiddleston had found time in his busy schedule next year for a production of Betrayal - especially if it's only a short run.

Of course, we could be wrong and this could actually be a stealth teaser for Hiddleston's Marvel show. Betrayal is one of Loki's favorite hobbies, after all. Either way, we'll keep you updated if there are any more details regarding this mysterious project.

More: Every Marvel TV Show Coming To The Disney Streaming Service

Source: Tom HiddlestonPedestrian